Good discussion. I don't know enough about market trends to speak with authority. I do know that trends and demographics are related in the big picture. Any new group that enters the knife world in sufficient numbers will influence the market. Examples might include women or post-military young adult males or Asians or the spawn of baby boomers or whatever. If there's enough of them they'll push the market toward their preferences.
Also, external forces are market drivers. The ivory ban for example, or legal pressures on blade length, concealed vs open carry etc. On top of all that stuff, over time those who enter as knife enthusiasts and stay around will experience an evolution of what they like, causing trends to shift.
In fact, I've got a new trend going in my life that is interesting. This no BS. As jeans have gotten tighter I've moved away from carrying knives in my pockets. I've started routinely wearing some of my custom belt knives with 3 inch blades out in the open and so far no issues. I may or may not be wearing a jacket or vest. But the blades are legal and I'm more comfortable in close fitting jeans.
Will this trend catch on? Will wearing custom belt knives with nice sheaths, materials and craftsmanship (and legal blades) become a thing? Any of my knife friends out there gonna join me? Come on, let's do it. Let's show some commitment. I don't want to be one of those guys who straps on a belt knife just for the knife show. Know what I mean?